Nicotiana is

Options

A. genus
B. species
C. variety
D. all of these

Answer

To answer the question "Nicotiana is:", we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Taxonomic Rank**:
- Nicotiana is a term used in biological classification. We need to determine its taxonomic rank.

2. **Understanding Genus**:
- In biological classification, a genus is a rank that is one level above species. It groups together species that are closely related.

3. **Determine the Family**:
- Nicotiana belongs to the family Solanaceae, which is commonly known as the nightshade or potato family.

4. **Identify Species under Nicotiana**:
- Two notable species under the genus Nicotiana are:
- Nicotiana tabacum (commonly known as the tobacco plant).
- Nicotiana africana (an African tobacco plant).

5. **Conclusion**:
- Since Nicotiana is a genus that contains multiple species, the correct answer to the question is that Nicotiana is a genus.

### Final Answer:
Nicotiana is a genus.

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